A wide variety of cosmetic compositions containing self-tanning agents have been used to increase the pigmentation of the skin. These compositions have been used to create artificial tans, bronzing the skin in a similar fashion to exposure to the sun. It would be preferable to incorporate skin care actives in self-tanning compositions to improve skin health whilst imparting colour. The self-tanning agents present in these compositions are typically quite unstable. This is thought to be due to the highly reactive nature of the self-tanning agents and/or the low pH that such products require. Degradation of the self-tanning agents with skin care actives in the formulation generally results in a reduction of available levels of self-tanning agent, and the production of undesirable colouring in the neat product during storage.
WO 94/04130, WO 94/13258, and WO 94/22419 disclose apparatus and methods for sunless tanning comprising an apparatus having two receptacles, one receptacle containing a fluid comprising dihydroxyacetone, the other receptacle containing a fluid formulation comprising respectively, primary amines, secondary polyamines, and amino acids, and dispensing means for simultaneously or sequentially providing desired amounts of the two fluids. However, the materials present in the second receptacle are secondary tanning agents or colour enhancers, and not ideal as skin care actives providing skin health benefits.
It is therefore desirable to provide cosmetic kits that colour or impart a natural-looking tan to the skin whilst simultaneously delivering skin actives to the skin, without unacceptable dicolouration of the product during storage, and without requiring high levels of the self-tanning agents or the skin care actives themselves.